Seam-trimmer for sewing-machines.



J. C. HINGE. SEAM TRIMMER FOR SEWING MACHINES.

APPLICATION FILED APR. 9. 1914.

Patented Mar. 28, 1916.

2 SHEETMS-SHEET I.

WITNESSES.

A TTORA/EY J. C. RINGE.

SEAM TRIMMER FOR SEWING MACHINES.

APPLICATION FILED APR. 9, 1914.

Patented Mar. 28, 1916;

' 2 SHSHEET 2. J .3. V v

rip.

JOHN G. RINGE, 0F BRIDGEPORT, CONNECTICUT, ASSIGNOR TO THE SINGERMANUFAC- TUBING COMPANY, A CORPORATION OF NEW JERSEY.

- SEAM-TRIMMER FOR SEWING-MACHINES.

Specification of Letters Patent.

Patented Mar. 25, 1916..

To all whom it may concern:

Be it known that 1, JOHN C. RINGE, a citizen of the United States,residing at Bridgeport, in the county of Fairfield and State ofConnecticut, have invented certain new and useful Improvements in Seam-Trimmers for Sewing-Machines, of which the following is a specification,reference being had therein to the accompanying drawmgs.

This invention relates to improvements in seam trimmers for sewingmachines and has for its object to provide atrimming mechanism adaptedto pierce and sever the fabric and to discontinue such severingoperation at any point in the line of scam formation at the will of theoperator during the stitching operation.

In the accompanying drawings, which form a part of the specification,Figure 1 is a front side elevation, partly in section, of one form ofcommercial sewing machine fitted with the present invention. Fig. 2, arear side elevation of Fig. 1; Fig. 3 a perspective of the trimmer-bladeand its actuating mechanism detached from the sewing machine; Fig. 4, aplan of the mechanism for controlling the lateral movements of theneedle. Fig. 5 a detail of certain elements shown in the previousfigure, later to be referred to. Fig. 6, a plan of the throatorneedle-plate, together with the ledger trimmer-blade. Fig. 7, asectional view of certain elements shown in Fig.3, later to be referredto. Fig. 8, upper and under side views, left to right respectively, ofthe clothpresser-foot. Fig. 9 an enlarged side elevation of thetrimmer-blade shown in Figs. 1 and 3. Fig. 10, a view illustrating thetrimming and zigzag sewing operations as when joining the free edge of afabric to the trimmed edge of an under ply.

The present construction preferably includes a stitch-forming mechanismcapable of effecting both zigzag and straight-away stitching, but it isto be understood thatit is not limited in its applicability, as thetrimmer mechanism is mounted independently of the actuating mechanism ofthe sewing machine exceptthat it is operatively connected with themainor needle-bar driving shaft.

Referring to the figures, 1 represents the sewing machine bed-plate uponwhich is mounted the bracket-arm comprising the arm standard 2 andarm-bracket 3, 4 the main or needle-bar driving shaft carrying the bandwheel 5 and operatively connected wlth the needle-carrying-bar 6 by thelink 7 8 denotes the needle, 9 the cloth-pressercarrying bar, 10 theneedle-thread take-up and 11 the thread tension.

12 represents the lower main or loop-taker drivmg shaft mounted in thetubular feedlift rock-shaft 18, as in earlier constructions, andprovided at its rear end with a pulley 13 connected by suitable belt 14with a pulley 15 secured on the main-shaft 1, the pulleys 13 and 15being of the ratio of one to two, thus giving to the shaft 12 two r0-tations to the one rotation of the shaft 4. To the forward end of theloop-taker drivmg shaft is suitably secured a beveled gear 16which'meshes with a like gear 17 (shown in dotted lines only, Fig. 1)fast on the looptaker shaft (not shown), common to the present form ofstitch-forming mechanism, said loop-taker shaft being provided with oneform of commonly employed loop-taker (not shown).

The herein employed cloth-feeding mechanism is substantially the same asis represented by U. S. Patent No. 1,020,089, dated March 12, 1912 to C.F. Gray, and as it has no particular bearing on the present constructionit is deemed suflicient to designate the parts illustrated by thenumeral 18.

19 represents a rock-shaft journaled in a suitable bearing formed in thebracket-arm and at its inner end carrying a crank-arm 20, its oppositeend being provided with a rigidly secured indexing lever 21 whose freeend is provided with an indexing blade 22.

23 denotes an indexing bracket having a hollow hub 24 secured by screw25 upon a suitable hub 26 (shown in dotted lines only, Fig. 4) formedintegral with the bracketarm, the upper end of said bracket beingprovided with an index 27, and slot 28, and through the latter andthrough a suitable opening formed in the upper end of the lever 21extends a securing bolt comprising a threaded portion 29 and a head ordisk portion 30, said threaded portion being provided with a nut 31,which latter, in connection with said disk portion, acts to secure theindex blade 22 against accidental movement.

-32 represents a link pivoted at 33 to the crank-shaft 20, its oppositeend being journaled on the stud-bolt 34 secured in the needle vibratingconnection 35-, the latter being fulcrumed on a stud 36 secured in theneedle-bar carrying frame 37 the opposite end of said connection beingforked to receive the cam 38 carried by the cam-shaft 39, the latteroperatively connected with the main-shaft 4 by spiral gear 40 carried bysaid main-shaft meshing with a like gear 41 carried by said cam-shaft,the ratio of said gears being as one to two, thus giving to thecam-shaft one rotation to two rotations of said main-shaft.

The cam 38 imparts to the connection 35, under all conditions ofstitch-formation, vibratory movements and the crank 20 and link 32 areof substantially the same length. It therefore results that therock-shaft 19 and crank-arm 20 constitute the fulcrum support for theswinging link 32, and that the axis of the pivotal point 33 may beshifted, through the manipulation of the index lever 21, from a positionintersecting an imaginary line drawn through the axes of the shaft 39,bolt 34 and stud 36 to a position above such line a distance sufficientto effect the desired amplitude of vibration of the needle.

It is to be understood that when the axis of the pivotal point 33intersects said imaginary line the connection 35 is given vibratorymovements only on the pivot 36, and that at such time the needleoccupies its zero or straight line stitching position, but when thepivotal point 33 is moved upward, as shown in dotted lines, Fig. 5, saidconnections, through the angle given said link with respect to saidimaginary line, is caused to transmit lateral movements to the needle ina direction to the left of its zero or straight line stitching position.

Referring now to the features in construction more directly connectedwith the invention, 42 represents a bracket secured by suitable screws(not shown) to the arm standard 3 and provided with a hub 43 into whichis journaled by screw 44 a short shaft 45 carrying a segment orrock-lever 46 provided with an under-cut guide-slot 47, said rock-leverbeing operatively connected with the main-shaft 4 by an eccentric 48 andeccentric strap connection 49.

50 denotes a cutter carrying rock bar provided at its forward or freeend with an ad justably secured trimmer-blade 51 provided with apiercing element 51, its opposite end being operatively connected by therock'lever connection 52 and ball joint connections, as 53, with saidrock-lever, the fulcrum for the cutter carrying rock bar comprising apin 54 provided with an eccentric 54, said pin being mounted in suitablebearings formed in the bracket 55 suitably secured to the under side ofthe bed-plate, the axial adjustment of .the pin effecting movements ofthe trimmer-blade across the line of seam formation, the screw 56 actingto secure said pin against accidental movement.

57 represents a trimmer-blade adjusting rock-shaft whose forward end isjournaled in a bracket 58 secured by screws, as 59, to

the head 60 of the arm bracket, its opposite crank-shaft carrying acrank-arm 68 piv- I oted to one end of a link 69 whose opposite end ispivotally connected with a ball joint stud 70 threaded into a slideblock 71 tracking the groove 47 formed in the rocklever 46.

72 denotes a spring-pressed plunger mounted in the bracket 42 andcoacting with notches as 73 (one only of which is shown) to hold thecrank-shaft 66 against oscillatory movements, the spring 74 acting inopposition to the spring-pressed plunger to yieldingly hold the head 75of the crankshaft 66 against the face of the bracket 42.

76 represents the needle or throat-plate provided with the usual needleopening 77 and feed-dog openings, as 78, 79 denotes the trimmer-ledgerblade secured by screw 80 to said throat-plate, its extended portion 81provided with the cutting edge 82 constructed to yield slightly to theaction of the trimmer-blade 51, normally located in the opening 83 insaid throat-plate.

84 represents a cloth-presser pivotally secured by pin 85 to thecloth-presser bracket 86, which latter is secured by screw 87 to thespring depressed cloth-presser carrying bar 9, the cloth-presser beingprovided with a fabric guiding wall 88 and an adjustably secured edgeguide 89, later to be referred to.

In the present embodiment of the invention the cutting edges of thetrimming members are preferably arranged to trim the fabric in line withthe zero or right hand line of stitches.

To effect a product represented by Fig. 10, the fabric 90 is passedbeneath the presser-foot to the action of the trimming andstitch-forming mechanisms as shown in the figure, the fabric 91 beingpassed from the supply over the inclined or turned-up portion 92 of thecloth-presser 84, through the opening 88 and beneath the rear endportion of the presser foot with its free edge 93 in guidingrelationship with the edge-- guide 89, the trimmer-blade 51 and saidedge-guide acting to guide the free edges 93 and 94 within the field ofthe lateral movements of the needle 8, thus causing the edges to bebound by the successive overedge stitches, the receiving end 92 of saidcloth-presser acting to guide the fabric 91 out of the field of actionof the fabric,

piercing element carried by the trimmerblade.

When it is desired to continue the stitching and suspend the trimmingoperation, the operator through the manipulation of the hand lever 62rocks the shaft 57 in the direction indicated by the arrow which,through the connections previously pointed out, rocks the crank-arm 68in a like direction a distance sufficient to cause the springpressedplunger 72 to register with one of the notches 73 or in position tocause the axis 95 of the upper of the ball joint connections 53 tointersect the axis of the short shaft carrying the rock-lever 46, suchadjustment of the axis 95 acting to suspend the rocking movements of thebar and owing to the guide slot 47 being inclined with respect to thevertical arrangement of the connection 52 the trimmer-blade piercingelement is carried below the plane of the throat-plate, or out ofaccidental engagement with the fabric. a Having thus set forth thenature of the invention what I claim herein is 1. In a sewing and fabrictrimming machine of the character described, the combination with astitch-forming and clothfeeding mechanism including a needle-plate, aneedle and a needle-carrying bar, of a trimming mechanism including aledger trimmer-blade carried by said needle-plate and a coactingtrimmer-blade, the cutting edge of the latter overhanging theneedleplate and provided with a piercing element arranged to pierce afabric in a direction opposite to that of the fabric piercing movementsof said needle.

2. In a sewing and fabric trimming machine of the character described,the combination with a stitch-forming and clothfeeding mechanismincluding a cloth-presser provided with an edge-guide and aguiding-wall, a needle-plate and a needle, of a trimming mechanismincluding a ledger trimmer-blade carried by said needle-plate and acoacting trimmer-blade, the cutting edge of the latter overhanging theneedleplate and provided with a piercing element arranged to pierce afabric in a direction opposite to that of the fabric piercing movementof said needle, said edge-guide and guiding wall acting to direct anoverlying fabric to the action of the needle outside the field of actionof said trimming mechanism.

3. In a sewing and fabric trimming ma- A chine of the characterdescribed, the combination with a stitch-forming and clothfeedingmechanism including a cloth-Presser provided with an edge-guide, aninclined receiving end and an opening for the passage of a fabric, aneedle-plate and a needlecarrying bar provided with a needle havinglateral movements efiecting an overedge seam, of a trimming mechanismincluding a ledger trimmer-blade carried by said needleplate and acoacting trimmer-blade, the cutting edge of the latter overhanging theneedle-plate and provided with a piercing element arranged to pierce afabric in a direction opposite to that of the fabric piercing movementsof said needle, said edge-guide acting to guide the free edge of anoverlying fabric through said opening in the presser-foot substantiallyin line with that portion of the overedge stitches anchored in anunderlying fabric, which latter is passed beneath said inclinedreceiving end of the Presser-foot in its travel to the action of theneedle and trimming elements.

4. In a sewing and fabric trimming machine of the character described,the combination with a stitch-forming and clothfeeding machanismincluding a needle-bar actuating shaft journaled in the sewing machinebracket-arm, a needle-plate, a needle and a needle-Carr ing bar, of atrimming mechanism inclu ing a ledger trimmerblade carried by saidneedle-plate and a coacting triimner-blade, the cutting edge of thelatter overhanging the needle-plate and provided with a piercing elementarranged to pierce a fabric in a direction opposite to that of thefabric piercing movements of said needle, and connections including asegment lever for operatively connecting said trimmer-blade with saidneedle-bar actuating shaft.

5. In a sewing and fabric trimming machine of the character described,the combination with a stitch-forming and clothfeeding mechanismincluding a needle-bar actuating shaft journaled in the sewing machinebracket-arm, a needle-plate, a needle and a needle-carrying bar, of atrimming mechanism including a ledger trimmer-blade carried by saidneedle-plate and a coacting trimmer-blade, the cutting edge of thelatter overhanging the needle-plate and provided with a piercing elementarranged to pierce a fabric in a direction opposite to that of thefabric piercing movements of said needle, and connections foroperatively connecting said trimmer-blade with said needle-bar actuatingshaft, said connections including a rocking cutter-carrying bar, asegment lever, an eccentric carried by said needle-bar actuating shaftoperatively connected with said segment lever, and operative connectionsbetween the latter and said cutter-carrying bar.

6. In a sewing and fabric trimming machine. of the character described,the com-' bination with a stitch-forming and clothfeeding mechanismincluding a needle-bar actuating shaft journaled in the sewing machinebracket-arm, a needle-plate, a needle and a needle-carrying bar, of atrimmingmechanism including a ledger trimmer-blade carried by saidneedle-plate and a coacting trimmer-blade, the cutting edge of thelatter overhanging the needle-plate and provided With a piercing elementarranged to pierce a fabric in a direction opposite to that of thefabric piercing movements of said needle, and connections including asegment lever for operatively connecting said trimmer-blade With saidneedle-bar actuating shaft and manually controlled means operating onsaid segment lever to suspend 15 the trimming action of saidtrimmer-blade.

In testimony whereof, I have signed my name to this specification, inthe presence of tWo subscribing Witnesses.

JOHN C. HINGE.

Witnesses:

N. H. HOYT, 4 STANLEY N. SMITH.

